[QUESTION] System.NotSupportedException: Any/All requires simple parameter on left side. - Querying nested array, how can I accomplish this?

LiteDB Version: 5.0.3

Hey guys, thanks for the work on LiteDB ! I am checking out if LiteDB might work for my use case. Thanks for the help!

My entities:

    public class TagEntryModel
    {
        public int Id { get; set; }
        public string Value { get; set; }
    }

    public class JobEntryModel
    {
        public int Id { get; set; }
        public string Company { get; set; }
        public string Title { get; set; }
        public string Subtitle { get; set; }
        public string Url { get; set; }
        public DateTime Date { get; set; }
        [BsonRef("JobEntryModel")] public List<TagEntryModel> Tags { get; set; } = new List<TagEntryModel>();
    }

Basically I want to be able to filter out job entries by tags, title, company and then order by date. Is this possible? What I have right now is:

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Threading.Tasks;
using LiteDB;

namespace LiteDbTestApp
{
    class Program
    {
       static void TestQuery()
        {
            if (File.Exists("test.db"))
                File.Delete("test.db");

            using var db = new LiteDatabase("Filename=test.db;Connection=Direct");
            var tagCollection = db.GetCollection<TagEntryModel>();
            var jobCollection = db.GetCollection<JobEntryModel>();

            var tag = new TagEntryModel {Value = "react"};
            tagCollection.Insert(tag);
            tagCollection.EnsureIndex(x => x.Value);

            var job = new JobEntryModel
                {Title = "random job title", Company = "random company", Tags = new List<TagEntryModel> {tag}};
            jobCollection.Insert(job);
            jobCollection.EnsureIndex(x => x.Tags);

            var findTags = new List<string> {"react"};
            var query = jobCollection.Query()
                .Include(x => x.Tags)
                .Where(x => x.Title.Contains("ti"))
                .Where(x => x.Tags.Select(model => model.Value).Any(b => findTags.Contains(b)))
                .OrderBy(x => x.Date)
                .Limit(50);

            var reader = query.ExecuteReader();
            var entities = reader.ToList();
            Console.WriteLine(entities.Count);
        }

        static async Task Main(string[] args)
        {
            TestQuery();
        }
}

Right now I am getting the following exception thrown:

Unhandled exception. System.NotSupportedException: Any/All requires simple parameter on left side. Eg: x.Customers.Select(c => c.Name).Any(n => n.StartsWith('J'))

[lbnascimento]

@atresnjo About the index, in your example you wouldn’t be able to do anything relevant with Tags because it is a reference to another collection, and you can only index information pertaining to the same collection.

Actually, I think it would be best for the Tags to be stored as embedded documents inside every JobEntryModel. It’s usually better to use embedded documents instead of references when modeling for a document-oriented database.

[lbnascimento]

@atresnjo The BsonRef attribute in Tags is wrong, it should be [BsonRef("TagEntryModel")]